Sim hangs at Quit to Desktop

Do you have the same issue if you follow the OP’s steps to reproduce it?
Yes, but not every time.

Provide extra information to complete the original description of the issue:
This usually happens when I do not quit immediately after a flight, but leave the game running while I work on something else, such as reading forum posts. When I return to quit, I cannot, so have to kill the app in task manager.

If relevant, provide additional screenshots/video:
N/A